

.box{
  svg {
    width: 0;
    height: 0;
  }
}

.loading {
  width: 200px;
  height: 200px;
  position: relative;
  filter: url(#gooey);
}

.loading span {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  display: block;
  animation: loading 4s ease-in-out infinite;
  /* var函数用来插入css变量的值，css变量名称以--开头 */
  animation-delay: calc(0.2s * var(--i));
}

.loading span::before {
  content: '';
  position: absolute;
  top: 0;
  left: calc(50% - 20px);
  width: 40px;
  height: 40px;
  background: linear-gradient(#fce4ec, #03a9f4);
  border-radius: 50%;
  box-shadow: 0 0 30px #03a9f4;
}

@keyframes loading {
  0% {
      transform: rotate(0deg);
  }

  50%,
  100% {
      transform: rotate(360deg);
  }
}

